Ultrasonography, computed tomography and magnetic resonance imaging of the bovine metacarpo/metatarsophalangeal joint.

The aims of the present study were to describe the normal ultrasonographic, magnetic resonance imaging (MRI) and computed tomographic (CT) appearances of the bovine metacarpo/metatarsophalangeal (MCP/MTP) joints and to assess the normal cross-sectional dimensions of the superficial (SDFT) and deep (DDFT) digital flexor tendons. A systematic ultrasound examination was performed on the MCP/MTP joints of 22 healthy cattle and two bovine cadavers, and the cross-sectional dimensions of the SDFT and DDFT were recorded. The cadaveric MCP/MTP joints (n=8) were scanned using a 16-slice multi-detector CT scanner and a 1.5 Tesla MRI scanner, injected with green latex and sectioned into transverse (n=4), sagittal (n=2) and dorsal (n=2) slices. Ultrasonographic, CT and MRI images were correlated with corresponding findings in anatomical dissections for the distal aspects of the third and fourth metacarpal/metatarsal bones, proximal aspects of the proximal phalanges, proximal sesamoid bones, lateral, common and medial digital extensor tendons, SDFT, DDFT, axial and abaxial collateral ligaments, suspensory, palmar/plantar, interdigital intersesamoidean and interdigital phalangosesamoidean ligaments, and collateral, cruciate and short sesamoidean ligaments. The axial and collateral sesamoidean ligaments could not be evaluated by ultrasonography. The articular cartilage, and the short and cruciate sesamoidean ligaments, were not identified in CT images. The cross-sectional dimensions of the SDFT and DDFT differed significantly between the forelimbs and hind limbs (P<0.05); there were no significant differences between the contralateral limbs. The annotated ultrasonographic, CT and MRI images are intended as a normal reference that could be useful for interpretation of clinical disease in the bovine MCP/MTP joint.

Computed Tomography of the Normal Bovine Tarsus.

The objective of this study was to provide a detailed multiplanar computed tomographic (CT) anatomic reference for the bovine tarsus. The tarsal regions from twelve healthy adult cow cadavers were scanned in both soft and bone windows via a 16-slice multidetector CT scanner. Tarsi were frozen at -20o C and sectioned to 10-mm-thick slices in transverse, dorsal and sagittal planes respecting the imaging protocol. The frozen sections were cleaned and then photographed. Anatomic structures were identified, labelled and compared with the corresponding CT images. The sagittal plane was indispensable for evaluation of bone contours, the dorsal plane was valuable in examination of the collateral ligaments, and both were beneficial for assessment of the tarsal joint articulations. CT images allowed excellent delineation between the cortex and medulla of bones, and the trabecular structure was clearly depicted. The tarsal soft tissues showed variable shades of grey, and the synovial fluid was the lowest attenuated structure. This study provided full assessment of the clinically relevant anatomic structures of the bovine tarsal joint. This technique may be of value when results from other diagnostic imaging techniques are indecisive. Images presented in this study should serve as a basic CT reference and assist in the interpretation of various bovine tarsal pathology.

Systematic arthroscopic investigation of the bovine stifle joint.

The objective of the present study was to establish a protocol for arthroscopic exploration of the bovine stifle joint using craniomedial, caudolateral and caudomedial approaches. An anatomic and arthroscopic study using 26 cadaveric limbs from 13 non-lame adult dairy cows was performed. The craniomedial approach was created between the middle and medial patellar ligaments to investigate the cranial pouches of the stifle joint. The inter-condylar eminence, the proximal aspect of the medial femoral trochlear ridge and the lateral aspect of the lateral femoral condyle were used as starting points for systematic examination of the medial femorotibial, the femoropatellar and the lateral femorotibial joints, respectively. The observed structures were: the suprapatellar pouch, articular surfaces of the patella, femoral trochlear ridges, cruciate ligaments, menisci, and the meniscotibial ligaments. The arthroscopic portal for the caudomedial femorotibial pouch was about 6-8 cm caudal to the medial collateral ligament. The proximal and distal caudolateral femorotibial pouches were explored 3 cm and 1.5 cm caudal to the ipsilateral collateral ligament, respectively. The observed structures were the caudal aspect of femoral condyles, menisci, caudal cruciate ligament, popliteal tendon and the meniscofemoral ligament. Restricted joint size and risk of common peroneal nerve damage were the major limitations for exploration of the caudal femorotibial compartments. The study described the arthroscopic portals and normal intra-articular anatomy of the bovine stifle joint but further investigations are warranted to validate these techniques in clinical cases.